package com.docMan.utils;


import java.security.MessageDigest;

/**
 * 采用MD5加密解密
 * @author tfq
 * @datetime 2011-10-13
 */
public class MD5Utils {

	/***
	 * MD5加码 生成32位md5码
	 */
	public static String string2MD5(String inStr){
		MessageDigest md5 = null;
		try{
			md5 = MessageDigest.getInstance("MD5");
		}catch (Exception e){
			System.out.println(e.toString());
			e.printStackTrace();
			return "";
		}
		char[] charArray = inStr.toCharArray();
		byte[] byteArray = new byte[charArray.length];

		for (int i = 0; i < charArray.length; i++)
			byteArray[i] = (byte) charArray[i];
		byte[] md5Bytes = md5.digest(byteArray);
		StringBuffer hexValue = new StringBuffer();
		for (int i = 0; i < md5Bytes.length; i++){
			int val = ((int) md5Bytes[i]) & 0xff;
			if (val < 16)
				hexValue.append("0");
			hexValue.append(Integer.toHexString(val));
		}
		return hexValue.toString();

	}

	/**
	 * 加密解密算法 执行一次加密，两次解密
	 */ 
	public static String convertMD5(String inStr){

		char[] a = inStr.toCharArray();
		for (int i = 0; i < a.length; i++){
			a[i] = (char) (a[i] ^ 't');
		}
		String s = new String(a);
		return s;

	}
	public static String getMD5(byte[] source)
	  {
	    String s = null;
	    char[] hexDigits = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
	    try
	    {
	      MessageDigest md = MessageDigest.getInstance("MD5");
	      md.update(source);
	      byte[] tmp = md.digest();

	      char[] str = new char[32];

	      int k = 0;
	      for (int i = 0; i < 16; ++i)
	      {
	        byte byte0 = tmp[i];
	        str[(k++)] = hexDigits[(byte0 >>> 4 & 0xF)];

	        str[(k++)] = hexDigits[(byte0 & 0xF)];
	      }
	      s = new String(str);
	    }
	    catch (Exception e) {
	      e.printStackTrace();
	    }
	    return s;
	  }
}
